Got a 1961 CJ-5 that has a problem. For a couple of months, the Willys will suddenly start lurching while being driven; usually for just a couple of seconds. But got worse the other day -- started lurching at about 35 mph, amp light went on and then engine cut out, with Jeep coasting to a stop. Restarted, drove a half mile, and same thing happened. Made it home, and pulled the battery to have it checked -- it was OK. Generator was rebuilt about 15 years ago; probably 10,000 miles on it since then. Anyone have any thoughts?